Looks a good idea in principle, but I would like to see a small length tested with heavy lorries going over it for a year or two first, especially if the surface it was laid on was uneven or subject to heave or shrinking as a lot of roads round this way are.

If it stood this test, and could be made for an economic price it really could revolutionise road construction.

Hairyloon

Joined: 20 Nov 2008Posts: 14981Location: Today I are mostly being in Yorkshire.

Posted: Sun May 25, 14 4:02 pm Post subject:

Where is the sense in paving the roads with PV when there is so much vacant roof space?

Certainly it is a good idea for some places: the configurable sports yard is pretty clever.

I've always been a bit skeptical of the idea, particularly as more efficient solar set-ups don't require all that much surface area of the world, if we were to have proper energy transmittance infrastructure (which the Chinese might start advancing).

Not a confidence booster that the findings of their research work stops in 2015.....

Also, this bit:

Quote:

Each full size hexagon panel measures four square feet, so there would be 15,840 panels per lane mile using a 12-foot wide lane. If each four of these produced 52397Wh in six months, then the same four would theoretically produce 104,794Wh per year.[emphasis mine] That's 26.1985kWh per year each. Multiply that by 15,840 panels, and the road would produce 414.984MWh per year per lane mile. This is with only 69-percent solar cell coverage. With 100-percent coverage, the output would be 601.426MWh per year per lane mile.

Is not very heartening to me. They're not specifying which six months they're multiplying off of. If it's the winter months, than great, the production will be even higher. But it seems like they're most likely to be taking summer months' production and just doubling it and painting a very overly optimistic picture. Now add short winter days, traffic (and its shading), and dust, and snow, and salt.

Their testing involves temperature swings, and "freezing it in a block of ice". As someone from an area with actual harsh winters, that doesn't cut it. These roads don't get frozen in a static block of ice, they have water seeping in to every nook and cranny and freezing, then being pushed around with plows and melting and freezing again, and salt corroding every bit of metal. There is a reason you don't find many old cars in New England - if they weren't garaged every winter they rust away!

Anyhoo, there's my skeptical rant. Really do hope they make advances that are useful for their own purposes (clearly there are many locales that don't have tough winters like mine), as well as advances that are useful for other developments (maybe they make a really solid modular roof tile design out of their product - though solar city may have beat them to the punch)

I realize that any startup has a big hurdle to get past before proving viability, and you need to push boundaries to make real advances. But I'm afraid I think the value here will be in the lessons from their work, rather than the dreams of the creators....

I haven't read the all gen, but if as I understand it, the road way is to generate electricity all year, then surely in the winter that "juice" could be used to save salting the roads? The amount of solar in winter is obviously limited, but 'they' tell me even a dull day will generate power albeit reduced. Now anything which saves salt being spread and rotting vehicles has to be all good? I expect my theory to be shot down.

I haven't read the all gen, but if as I understand it, the road way is to generate electricity all year, then surely in the winter that "juice" could be used to save salting the roads? The amount of solar in winter is obviously limited, but 'they' tell me even a dull day will generate power albeit reduced. Now anything which saves salt being spread and rotting vehicles has to be all good? I expect my theory to be shot down.

Let's just play it out.
Here's my guess:
If the roads are snow covered (and maybe more of a problem: at night which is maybe 2/3 - 3/4 of the short winter day) there is no light for PV production, so any time there is heavy snow the power is coming from elsewhere on the grid to heat them so that they can produce PV power again. It would be electric resistance heat, which is a fairly big energy draw. Especially since the evaporating snow/ice melt will be cooling the road surface at the same time.
It would require some sort of monitoring to know when to turn on (maybe any temp near or below freezing with the presence of moisture?)

I definitely like the idea of abandoning salting roads, and I really want to see more solar get installed everywhere.

However, this just seems like a difficult way to do solar in general.

I guess I'm just more of the opinion:
"let's put solar on top of all of our existing many acres of parking lots and parking garages before we try to completely re-invent our road infrastructure"